13481681 has 2 divisors, whose sum is σ = 13481682. Its totient is φ = 13481680.

The previous prime is 13481639. The next prime is 13481687. The reversal of 13481681 is 18618431.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13140625 + 341056 = 3625^2 + 584^2 .

It is a cyclic number.

It is not a de Polignac number, because 13481681 - 2⁶ = 13481617 is a prime.

It is a super-2 number, since 2×13481681² = 363511445171522, which contains 22 as substring.

It is a nialpdrome in base 8.

It is not a weakly prime, because it can be changed into another prime (13481687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6740840 + 6740841.

It is an arithmetic number, because the mean of its divisors is an integer number (6740841).

Almost surely, 2^13481681 is an apocalyptic number.

It is an amenable number.

13481681 is a deficient number, since it is larger than the sum of its proper divisors (1).

13481681 is an equidigital number, since it uses as much as digits as its factorization.

13481681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 32.

The square root of 13481681 is about 3671.7408677629. The cubic root of 13481681 is about 238.0024068208.

The spelling of 13481681 in words is "thirteen million, four hundred eighty-one thousand, six hundred eighty-one".